From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 2BE4BE732C0 for ; Thu, 28 Sep 2023 11:17:35 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231778AbjI1LRe (ORCPT ); Thu, 28 Sep 2023 07:17:34 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:39140 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232786AbjI1LQu (ORCPT ); Thu, 28 Sep 2023 07:16:50 -0400 Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by lindbergh.monkeyblade.net (Postfix) with ESMTP id 9CA742B9C3; Thu, 28 Sep 2023 04:12:21 -0700 (PDT) Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 2C9D51FB; Thu, 28 Sep 2023 04:12:34 -0700 (PDT) Received: from bogus (e103737-lin.cambridge.arm.com [10.1.197.49]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 6BFE93F5A1; Thu, 28 Sep 2023 04:11:54 -0700 (PDT) Date: Thu, 28 Sep 2023 12:11:52 +0100 From: Sudeep Holla To: "lihuisong (C)" Cc: linux-hwmon@vger.kernel.org, linux-kernel@vger.kernel.org, linux-i2c@vger.kernel.org, linux-acpi@vger.kernel.org, "Rafael J. Wysocki" , Andi Shyti , Jean Delvare , Guenter Roeck Subject: Re: [PATCH 1/3] ACPI: PCC: Add PCC shared memory region command and status bitfields Message-ID: <20230928111152.cctl3m5rwtopyg2g@bogus> References: <20230926-pcc_defines-v1-0-0f925a1658fd@arm.com> <20230926-pcc_defines-v1-1-0f925a1658fd@arm.com> <20230927135909.6rssuywmj4k3odex@bogus> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: Precedence: bulk List-ID: X-Mailing-List: linux-i2c@vger.kernel.org On Thu, Sep 28, 2023 at 11:49:25AM +0800, lihuisong (C) wrote: > > 在 2023/9/27 21:59, Sudeep Holla 写道: > > On Wed, Sep 27, 2023 at 10:07:15AM +0800, lihuisong (C) wrote: [...] > > > > +/* Generic Communications Channel Shared Memory Region */ > > > > +#define PCC_SIGNATURE 0x50424300 > > > Why is this signature 0x50424300? > > It is as per the specification. > > > > > In ACPI spec, this signature is all 0x50434303. > > No, not exactly. It is just an example. > > The PCC signature - The signature of a subspace is computed by a bitwise-or > > of the value 0x50434300 with the subspace ID. For example, subspace 3 has > > signature 0x50434303 > Sorry for my mistake. I know this. > I mean, why doesn't the following macro follow spec and define this > signature as 0x504*3*430. > "#define PCC_SIGNATURE **0x504*2*4300*"* > Because it seems that all version of ACPI spec is 0x5043430. Sorry my mistake. Stupidly the existing drivers have it wrong and I just copied them without paying much attention. I will fix it up. It must be 0x50434300 instead of 0x50424300. If you have no other comments, can you please ack v2 patch 4/4 changing soc kunpeng_hccs driver. I will fixup the PCC_SIGNATURE and send it as part of my PR to Rafael. Refer [1] for the change in PCC_SIGNATURE, sorry for missing the point. I was confident that the existing code is correct :), but I am wrong. -- Regards, Sudeep [1] https://git.kernel.org/sudeep.holla/l/pcc_defines